The number you use also depends on the bobbin. My friend and myself both have bernina440 nq. And they fill a bobbin different amounts. Mine fills right to the top before stopping. Hers stops about 1/16" short of the top. Also mine works fine from a full bobbin another friend with the same machine finds she has to stop short of the top as her machine doesn't sew properly with a full bobbin. Just these 3 machines would give totally different amounts.